GB2199107A

GB2199107A - Apparatus for producing twist in a shaft

Info

Publication number: GB2199107A
Application number: GB08720158A
Authority: GB
Inventors: William Duncan Gordon
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-09-05
Filing date: 1987-08-26
Publication date: 1988-06-29
Also published as: GB8720158D0

Abstract

Apparatus (18) for producing twist in a shaft, which apparatus (18) comprises at least one load-receiving member (20, 22) to which a load is to be applied, at least one shaft (28), and at least one transfer member (32, 34) which is for transferring the load of the load-receiving member (20, 22) to the shaft (28) and which is connected to the shaft (28) such that in use of the apparatus (18) a load applied to the load-receiving member (20, 22) causes the load-receiving member (20, 22) to rotate the transfer member (32, 34) which then provides a twist in the shaft (28). <IMAGE>

Description

APPARATUS FOR PRODUCING TORQUE This invention relates to apparatus for producing torque. More especially, this invention relates to apparatus for providing a rotating force through a shaft.

The majority of engines involve apparatus in which a shaft is rotated. The rotation of the shaft is a convenient way of converting energy from the engine into a more readily useable form, that is, in the form of a rotating shaft. The engines may be coupled to, for example, electrical generators, dynamos, water pumps and air compressors and all of these pieces of apparatus are enabled to function by attaching them to a rotating shaft.

Electrical motors have the disadvantage of needing to be connected to an electrical power supply. The majority of electrical motors exist for the purpose of rotating a shaft, again as a convenient means of driving other appliances such, for example,as vacuum cleaners, refridgerators, freezers, washing machines, food mixers, air conditioning fans and machine tools.

It is an aim of the present invention to provide apparatus for producing torque, which apparatus may be used in place of existing pieces of apparatus employing a rotating shaft.

Accordingly, this invention provides apparatus for producing torque, which apparatus comprises at least one load-receiving member to which a load is to be applied, at least one output shaft, and at least one transfer member which is for transferring the load from the load-receiving member to the output shaft and which is connected to the output shaft such that in use of the apparatus a load applied to the load-receiving member causes the load-receiving member to rotate the transfer member which then rotates the output shaft.

The load-receiving member may be mounted for rotation about a support member which is fixed to the output shaft.

Preferably, there are two load-receiving members.

Also preferably, there are two transfer members, the two transfer members being such that they extend away from each other on opposite sides of the output shaft, and the two transfer members being connected to the output shaft such that they cannot move with respect to the output shaft.

The or each load-receiving member may operate on a steadying-member which is connected to the output shaft such that it is rotateable with respect to the output shaft.

The output shaft will usually be mounted for rotation in a mounting frame. The mounting frame may be of any desired shape and size and it may be provided with any desired fixing means for fixing the mounting frame in any desired position.

The apparatus of the invention preferably includes resilient means for maintaining at least some of the rotational movement of the load-receiving member, the amount of torque available from the output shaft being dependent upon the amount of compression or tension in the resilient means.

The resilient means may be at least one coil spring.

Preferably, the resilient means comprises a pair of coil springs for the or each load-receiving member, the coil springs both acting in the same manner on the -load-receiving member.

The. apparatus of the present invention may advantageously include adjustor means.

Preferably, the adjustor means is a screw threaded adjustor means.

Embodiments of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figures 1,2 and 3 are diagrams given for use in understanding the operating principle of the apparatus of the invention; Figure 4 is a simplified isometric view showing first apparatus for producing torque; Figure 5 is a longitudinal section through second apparatus for producing torque; and Figure 6 is a top view of the apparatus shown in Figure 5.

Referring to Figure 1, there is shown a bar 2 which may be of any desired material, for example a metal.

The bar 2 is shown being twisted along its length by a twisting force or torque T1. , The torque T1 is applied at each end of the bar 2 and the direction of rotation of the torque T1 at each end of the bar 2 is shown by arrows 4,6.

As can be seen from the arrows 4,6, the torque at one end of the bar 2 is acting in the opposite direction to the torque at the other end of the bar 2. The torque at both ends of the bar 2 has the same value so that a balance is maintained in the bar 2.

Referring now to Figure 2, there is shown a bar 8 which is of square cross section. If the bar 8 is similarly loaded at each end with the torque T1 then the torque T1 at each end acts as shown by the arrows on the ends of the bar 8.

The forces due to the torque T1 in the ends of the bar 8 can be balanced out by a new torque T2 which can be caused to act perpendicular to the plane of rotation of the torque T1. Such an arrangement is shown in Figure 3. In Figure 3, the torsional load that was in the ends 10,12 is now at the ends 14,16. The torque T1 is reduced to zero.

The principle shown in Figures 1 to 3 and especially in Figure 3 can be utilised in apparatus for producing torque as shown in Figure 4. Referring to Figure 4, there is shown apparatus 18 for producing torque. The apparatus 18 comprises two load-receiving members 20,22 to which a load is applied in the direction of arrows 24,26 respectively.

The apparatus 18 also comprises an output shaft 28 which is able to rotate in the direction of arrow 30. The apparatus 18 further comprises two transfer members 32,34 which are for transferring the load from the load-receiving members 20, 22 to the output shaft 28. The transfer members 32,34 are connected to the output shaft 28 such that in use of the apparatus 2, a load applied to the load-receiving members 20,22 causes the load-receiving members 20,22 to rotate the transfer members 32,34 in the direction of the arrows 36,38, which then causes rotation of the output shaft 28.

The load-receiving members 20,22 are shaped as shown in Figure 4 and they are mounted for rotation about support members 40,42 respectively. The support members 40,42 can be two separate shafts which are welded as shown for example by weld 44 to the outside of the output shaft 28. Alternatively, the support members 40,42 can be formed by a single shaft which passes through an aperture in the output shaft 28 and which is welded in position, for example by the weld 44.

As can be seen from Figure 4, the two transfer members 32,34 extend away from each other on opposite sides of the output shaft 28. Again, the transfer members 32,34 can be formed by two separate shafts which are welded to the outside of the output shaft 28, for example by weld 46.

Alternatively, the two transfer members 32,34 can be formed by opposite end portions of a single shaft which passes through an aperture in the output shaft 28 in which it is held in position by a weld such as the weld 46.

The load-receiving members 20,22 operate on steadying members 48,50 respectively. The steadying members 48,50 are joined to the output shaft 28 by means of a bearing 52 so that the steadying members 48,50 are rotateable with respect to the output shaft 28. The direction of rotation of the steadying members 48,50 is shown by arrows 54,56.

The output shaft 28 is mounted in bearings 58,60 and these bearings 58,60 are provided in upstanding end members 62,64. The end members 62,64 form part of a mounting frame 66 which includes a base plate 68.

The load-receiving members 20,22 are provided with recessed portions 70 which receive as shown the ends 72 of the load transfer members 32,34 and the steadying members 48, 50. The load-receiving members 20,22 are also provided with arm portions 74,76 to which the load is applied as shown by the arrows 24,26.

The load-receiving members 20,22 are mounted on the support members 40,42 via bearings 78,80. The bearings 78, 80 enable the load-receiving members 20,22 to rotate under the action of loads applied to the arm portions 74,76 in the direction of the arrows 24,26. It will generally be seen that loads applied to the arm portions 74,76 in the direction of the arrows 24,26. result in rotation of the load-receiving members 20,22 and this rotation is applied to the transfer members 32,34 and also to the steadying members 48,50. Because the transfer members 52,34 are fixed to the output shaft 28 and cannot rotate with. respect to the output shaft 28, the rotation of the transfer members 32,54 gets transferred to the output shaft 28 which is caused to rotate in the direction of the arrow 30.

Referring now to Figures 5 and 6, there is shown second apparatus 82 for producing torque. The apparatus 82 comprises a pair of load-receiving members 84, 86 which are in the form of discs as shown. The load-receiving members 84,86 are for receiving a load as will be described in more detail hereinbelow.

The apparatus 82 has an output shaft 88.

The apparatus 82 further comprises a pair of transfer members 90,92. These transfer members 90,92 are in effect formed by opposite ends of a single shaft 94. The transfer members 90,92 are provided with reduced diameter ends 96,98 and these ends 96,98 fit in recesses 100,102 formed in the load-receiving members 84,86. The apparatus 82 operates similarly to the apparatus 18 shown in Figure 4 so that a oad applied to the load-receiving members 84,86 causes the load-receiving members 84,86 to rotate the transfer members 90,92. This then causes rotation of the output shaft 88.

The load-receiving members 84,86 are mounted on bearings 104,106 so that the load-receiving members 84,86 are mounted for rotation about a support member 108 which is fixed to the output shaft 88 by a fixing 110. The fixing 110 ensures that the support member 108 cannot rotate with respect to the output shaft 88.

The apparatus 82 is provided with two steadying members 112,114 which are acted upon by the load-receiving members 84,86. More specifically, the steadying members 112,114 have reduced diameter portions 116,118 respectively which operate in recesses 120,122 in the load-receiving members 84,86. The steadying members 112,114 are mounted on a bearing 124 so that the steadying members 112,114 are able to rotate with respect to the output shaft 88.

The apparatus 82 has a frame 126 and the frame 126 includes upstanding end members 128,130 which are bolted by bolts 132 to a base plate 134. The end members 128,130 are provided with bearings 136,138 and these bearings 136, 138 rotateably support the output shaft 88 as shown. The output shaft 88 is held in position by means of tightening nuts 140,142. The frame 126 also includes a support member 144 which is connected by a connecting device 146 to the output shaft 88. Rivets or other securing devices 148 connect the support member 144 to a cylindrical frame part 150. The end of the cylindrical frame part 150 remote from the support member 144 is connected to the bearings 104,106 as shown.

The apparatus 82 includes resilient means in the form of two pairs of coil springs 152,154 which act on the upper load-receiving member 84, and 156,158 which act on the lower load-receiving member 86. The springs 152,154 and 156,158 are for maintaining at least some of the rotational movement of the load-receiving members 84,86.. The amount of torque available from the output shaft 88 is dependent upon the amount of compression or tension in the resilient means exemplified by the springs 152, 154 and 156,158.

The apparatus 82 includes adjustor means in the form of screw threaded adjustor means 160. The adjustor means 160 includes a hand rotatable knob 162 which can be screwed up and down a threaded shaft 164. As the knob 162 is screwed up and down the shaft 164, it acts on a plate member 166 such that the plate member 166 presses with more or less force against springs 170. The springs 170 abut against a plate member 172. The plate member 172 itself abuts against a plate member 174 through a thrust bearing 176. The plate member 166 slides up and down on shafts 178 which are mounted on and project outwardly from the plate member 172. The shafts 178 also serve to guide the springs 170.

Lugs 180 are mounted on the plate member 174 and each lug 180 is provided with an arm member 184. As can be seen from Figures 5 and 6, one arm member 184 acts on the luad-receiving member 84, whilst the other arm member 184 acts on the load-receiving member 86. The arm members 184 are connected to the load-receiving members 84,86 by means of pivotable connections 186.

Lugs 188 are provided on the plate member 174 for receiving one end of the springs 158 as shown. Similarly, lugs 190 are provided on the support member 144 for receiving one end of the springs 154,156. Capstan members 192 are provided as shown for receiving the other ends of the springs 152, 154, 156, 158 as can most clearly be seen in Figure 6.

In use of the apparatus 82 shown in Figures 5 and 6, the adjustor means 160 enables the output of the apparatus 82 to be.varied from zero to a maximum. Basically it will be seen that the apparatus 82 is such that the outer ends of the transfer members 90,92 are twisted within their elastic limit and the twist achieved can be held by the load applied to the load-receiving members 84,86. The output available from the apparatus 82 depends upon the amount of residual twist held in the rotating transfer members 90,92.

The arm members 184 as can be seen most clearly from Figure 6 are attached near the periphery of the load-receiving members 84,86 and they extend, as shown, substantially tangentally to the load-receiving members 84,86. By virtue of the thrust bearing 176, the plate member 174 is free to rotate on the output shaft 88. The apparatus 82 in fact has three of the shafts 178 and these three shafts 178 ensure smooth axially movement of the plate member 174 when the knob 162 is screwed in or out as required for adjustment.

Although the plate member 174 is free to rotate, it is held firmly in the apparatus 82 against the plate member 172 which is held stationary.

It is to be appreciated that the embodiments of the invention described above with reference to the accompanying drawing have been given by way of example only and that modifications may be effected. Thus, for example, the loadreceiving members 20,22 and 84,86 may be shaped differently than shown in the drawings.

Claims

1. Apparatus for producing torque which apparatus comprises at least one load-receiving member to which a load is to be applied, at least one output shaft, and at least one transfer member which is for transferring the load from the load-receiving member to the output shaft and which is connected to the output shaft such that in use of the apparatus a load applied to the load-receiving member causes the load-receiving member to rotate the transfer member which then rotates the output shaft.

2. Apparatus according to claim 1 in which the load-receiving member is mounted for rotation about a support member which is fixed to the output shaft.

3. Apparatus according to claim 1 or claim 2 in which there are two load-receiving members.

4. Apparatus according to any one of the preceding claims in which there are two transfer members, the two transfer members being such that they extend away from each other on opposite sides of the output shaft and the two transfer members being connected to the output shaft such that they cannot move with respect to the output shaft.

5. Apparatus according to any one of the preceding claims in which the or each load-receiving member operates on a steadying member which is connected to the output shaft such that it is rotateable with respect to the output shaft.

6. Apparatus according to any one of the preceding claims in which the output shaft is mounted for rotation in a mounting frame.

7. Apparatus according to any one of the preceding claims and including resilient means for maintaining at least some of the rotational movement of the load-receiving member, the amount of torque available from the output shaft being dependent upon the amount of compression or tension in the resilient means.

8. Apparatus according to claim 7 in which the resilient means comprises at least one coil spring.

9. Apparatus according to claim 8 in which the resilient means comprises a pair of coil springs for the or each load-receiving member, the coil springs both acting in the same manner on the load-receiving member.

Apparatus according to any one of the preceding claims and including adjustor means.

11. Apparatus according to claim 10 in which the adjustor means is a screw threaded adjustor means.

12. Apparatus for producing torque, substantially as herein described with reference to Figure 4 or to Figures 5 and 6 of the accompanying drawings.